fix(completion): handle NUL-separated package candidates

[Scott-Nx]

Fix Bash completion warning caused by NUL-separated package candidates from paru -Pc.

Problem

When completing package names with Bash completion, for example:

paru -S gpu-screen-reco<Tab>

Bash prints:

bash: warning: command substitution: ignored null byte in input

The warning comes from _paru_pkg():

_arch_compgen "$(paru -Pc)"

paru -Pc emits NUL bytes. Bash command substitution cannot preserve NUL bytes, so Bash drops them and prints the warning.

On my system:

$ paru -Pc | LC_ALL=C tr -cd '\000' | wc -c
1734

Fix

Convert NUL bytes to newlines before passing the output into _arch_compgen:

_arch_compgen "$(paru -Pc | tr '\000' '\n')"

This preserves candidate separation and avoids the Bash warning.

Testing

Confirmed that paru -Pc emits NUL bytes:

$ paru -Pc | LC_ALL=C tr -cd '\000' | wc -c
1734

Confirmed that converting NUL bytes to newlines removes them:

$ paru -Pc | tr '\000' '\n' | LC_ALL=C tr -cd '\000' | wc -c
0

After applying the patch, Bash completion works without the warning:

paru -S gpu-screen-reco<Tab>

Expected candidates are shown:

$ paru -S gpu-screen-recorder
gpu-screen-recorder               gpu-screen-recorder-notification  gpu-screen-recorder-ui

[pfeifferj]

I can't reproduce the issue you're trying to fix with this PR

[Scott-Nx]

I think this may depend on whether paru -Pc emits NUL-separated candidates on the local system.

On my machine, _paru_pkg() currently does this:

_arch_compgen "$(paru -Pc)"

and paru -Pc contains NUL bytes:

$ paru -Pc | LC_ALL=C tr -cd '\000' | wc -c
1734

Bash command substitution cannot preserve NUL bytes, so Bash drops them and prints:

bash: warning: command substitution: ignored null byte in input

Could you check whether paru -Pc contains NUL bytes on your system?

paru -Pc | LC_ALL=C tr -cd '\000' | wc -c

If this returns 0, that would explain why you cannot reproduce the warning locally. If it returns a non-zero value, the warning should be reproducible when the completion path calls _paru_pkg().

This patch is mostly a defensive normalization rather than a behavior change. For systems where paru -Pc already produces shell-safe output, completion behavior should stay effectively the same. For systems where paru -Pc emits NUL-separated output, converting NUL bytes to newlines before Bash command substitution avoids the warning while keeping candidate separation usable for completion.

The patch changes the input passed to _arch_compgen from:

_arch_compgen "$(paru -Pc)"

to:

_arch_compgen "$(paru -Pc | tr '\000' '\n')"

TL;DR

This is not intended to change completion behavior for systems that already work. It only normalizes NUL-separated output before Bash command substitution, because Bash cannot preserve NUL bytes anyway.

[pfeifferj]

my guess is that your ~/.cache/paru/packages.aur is corrupted with raw gzip bytes

[sparshjain265]

I am getting the same warning as @Scott-Nx. paru -Pc | LC_ALL=C tr -cd '\000' | wc -c reveals I have 1713 NUL bytes, and this fix gets rid of these warnings for me without any noticeable incorrectness in the behaviour.